This invention relates to an indicator, an associated package and associated methods.
Indicators useful for telling whether a product (such as a food product) has been exposed to high temperature or undesirably long shelf time or both are known. See, U.S. Pat. No. 3,999,946. Generally, these indicators involve providing a label that changes colors in order to indicate these undesirable occurrences. The label color then is matched to a chart or a table that shows the different possible colors. The color of the label is compared to a complementary color on the chart to see if the product is acceptable.
U.S. Pat. No. 4,538,926 shows a temperature indicator for use with wine in which the indicator is adjacent to a scale having red and violet colors. The scale acts as a thermometer, telling the user whether the environmental temperature is too hot or too cold for the wine.
Despite the availability of these products, there is still a need for an easy to use indicator that gives the consumer a clear acceptable/unacceptable indication of the freshness or suitability of products contained in a package. The indicator should also remove all "guess-work" or judgment from the consumer with regard to whether the product contained in the package is acceptable or not.